HIV can be successfully measured in urethral fluids and urine that are obtained after prostatic massage, an international team of investigators report in the online edition of Sexually Transmitted Infections.
Levels of HIV in fluids and urine after prostatic massage were correlated with those observed in semen samples which were yielded by masturbation.
Most of the study participants found prostatic massage acceptable, and the investigators believe the procedure could be useful for individuals participating in HIV transmission studies who are unable to provide semen samples.
The study also provided some insights into the possible impact of antiretroviral therapy on infectiousness. None of the patients who were taking HIV treatment had detectable virus in either post-massage fluids/urine or semen.
Investigators from Kenya, the US and UK had found previously that levels of HIV in fluids and urine after prostatic massage were correlated with those in semen. They wished to see how acceptable and feasible the collection of samples after prostate massage was in HIV-positive men.
They therefore designed a prospective study involving 47 patients in Kenya. These men had a median age of 31 years, 75% reported that they had sex with other men, with two-thirds also indicating that they had engaged in transactional sex.
Physicians were trained to perform prostate massage and after a maximum of five minutes, fluid was collected from the urethra and then men were asked to provide a urine sample. One week later, participants provide a semen sample. Individuals were instructed to abstain from any kind of sex for 48 hours before prostate massage and the production of semen.
Blood samples were also collected to see if levels of HIV correlated those observed in fluids/urine/semen.
Computer-assisted questionnaires were used to assess the acceptability of prostate massage and masturbation to provide semen samples.
The patients had quarterly assessments between 2007 and 2009.
Three-quarters of men reported that they abstained from sex for the specified period before prostate massage, with 95% reporting abstinence before the provision of semen samples.
Only 8% of men reported reservations about prostate massage and fluid/urine collection, and 6% said that they had misgivings about masturbating to provide semen samples.
A fifth of men experienced discomfort during prostate massage.
All the men who successfully provided samples after massage said that they would be willing to undergo this procedure again. Sex with other men and transactional sex work were both associated with the successful provision of samples. The performance of the massage by a female clinician was associated with a significantly lower rate of success (p = 0.014).
Pain, embarrassment and discomfort were associated with reluctance to undergo prostate massage. Heterosexual men were more likely than individuals reporting sex with other men to report reservations or discomfort about the procedure. But the investigators note, “the small number of heterosexual participants limited our evaluation of this factor.”
Prostate massage resulted in fluid/urine collection at 64% of visits, significantly lower than the 81% success rate for semen collection (p < 0.01). However, three-quarters of men successfully provided both types of fluid on at least one occasion.
At the initial assessment, HIV was successfully quantified in both post-massage fluid/urine and semen in 28%, in fluid/urine alone in 7% and in semen alone in 17%.
HIV was detectable in paired semen/blood samples for 45% of men.
Ten men were taking antiretroviral therapy, and three had virus detected in their blood. However, none had detectable viral load in either post-massage fluid/urine or semen.
There was a high level of concordance between the results of the initial assessment and those obtained at follow-up visits. All the men treated with antiretroviral drugs maintained an undetectable viral load in both post-massage fluid/urine and semen.
For those with detectable virus, HIV levels in fluid/urine, semen and blood were correlated.
“Post-prostatic massage fluid/urine [post-PMF/U] represents a valid alternative approach to assess HIV-1 shedding in semen,” comment the investigators.
They suggest “for men in certain circumstances (e.g., during wound healing after male circumcision, when a painful ulcer is present, in men with low CD4 cell counts, in men with difficulty providing semen), post-PMF/U may represent a valuable alternative to semen collection in research settings requiring genitourinary sampling.”
Graham SM et al. Post-prostatic massage fluid/urine as an alternative to semen for studying male genitourinary HIV-1 shedding. Sex Transm Infect online edition: DOI:10.1136/sti.2010.047118, 2011 (click here for the free abstract).